Mechanical trip control for presses



April 29, 1952 v. GEORGEFF 2,594,909

MECHANICAL TRIP CONTROL FOR PRESSES Filed Nov. 3, 1947 4 Sheets-Sheet le2 24 l6 Him 34 I l2 "[1 IP55 a ll 46 VHS/L GEOEGEFF HTTORNEY April 29,1952 v. GEORGEFF MECHANICAL TRIP CONTROL FOR PRESSES 4 Sheets-Sheet 2Filed Nov. 3, 1947 IN V EN TOR VHS/L GEOPGEFF BY L HTTORNEY April 29,1952 v. GEORGEFF MECHANICAL TRIP CONTROL FOR PRESSES 4 Sheets-Sheet 3Filed NOV. 5, 1947 INVENTOR April 29, 1952 v. GEORGEFF MECHANICAL TRIPCONTROL FOR PRESSES 4 SheetsSheet 4 Filed Nov. 5, 1947 INVENTOR PatentedApr. 29, 1952 MECHANICAL TRIP CONTROL FOR PRESSES Vasil Georgefi,Chicago, 111., assignor to Danly Machine Specialties, Inc., Chicago,111., a corporation of Illinois- Application November 3, 1947, SerialNo. 783,748 5 Claims. (Cl. 192 13s) My invention relates to a mechanicaltrip control for presses and more particularly, to an improvedmechanical control for power presses, enabling single stroke, continuousand inching operations of a power press through a completely mechanicalcontrol system.

In the operation of power presses it is neces sary to control the pressto permit it to go through a. single cycle once upon the actuation ofthe control in order to permit the finished work to be removed and a newblank to be inserted. In some operations, it is desirable that the pressrun continuously, there being sufficient time to feed a strip of stockbetween the actual work performing steps. Then, too, in removing andinserting dies or in adjusting dies, a control must be able to inch andstop it at any desired part of its cycle. Most of the controls forpresses involve the use of electrical systems, comprising a plurality ofrelays and complicated electrical wiring. These systems are not onlyexpensive but are susceptible to frequent breakdowns resulting fromshort circuits or deterioration of the contact parts of the relays.Their complicated nature is such that when trouble develops it is a timeconsuming task, first to locate the trouble, and frequently in itsrepair.

One object of my invention is to provide an improved mechanical tripcontrol for presses capable of controlling the press for a single strokeU operation, continuous operation and inching operation as desired.

Another object of my invention is to provide a mechanical trip controlfor presses which when set for single stroke operation will not repeatits cycle.

Another object of my invention is to provide a safe, completelymechanical control for presses which is certain in its operation andcapable of operating for long periods of time without repair orbreakdown.

A further object of my invention is to provide a mechanical trip controlfor presses which is simple in its operation and inexpensive tomanufacture.

Other and further objects of my invention will appear from the followingdescription:

In accompanying drawings which form part of the instant specificationand which are to be read in conjunction therewith and in which likereference numerals are used to indicate like parts in the views:

Fig. l is a side elevation of a power press fitted with a mechanicaltrip control according to one embodiment of my invention.

Fig.. 2 is a front elevation of a portion of the press shown in Fig. ldrawn onan enlarged scale with parts brokenaway showing the mechanicaltrip control shown in Fig. 1.

Fig. 3 is an elevation viewed along the line 33 of Fig. 2 showing theposition of parts. when the press is stopped and in idle position.

Fig. 4 is a View similar to Fig. 3 showing the parts with the controladjusted for a single stroke operation with the foot pedal in operatingpost tion.

Fig. 5 is a view similar to Fig. 3 showing the parts in the positionthey occupy at the instant after the control has operated to stop thepress with single stroke setting.

Fig. 6 is a view similar to Fig. 3 with the control set for continuousoperation showing the position of parts during the operation of thepress.

Fig. 7 is a view similar to Fig. 3 with the controls set for continuousoperation showing the position of parts'during the stopping of thepress.

Fig. 8 is a view similar to Fig. 3 showing the position of parts duringthe inching of the press.

Fig. 9 is a front elevation of the lower part of the press shown in Fig.1 drawn on a smaller scale showing the control foot pedal and pedallatch.

In general my invention contemplates the provision of a control systemoperating through the control of the valve governing the compressed airsupply to the clutch and brake assembly of the press. In power pressesit is customary to employ a continuously running flywheel adapted to heclutched to the operating train of the press or to be unclutchedtherefrom with the simultaneous setting of the brake.

In my control system I provide a linkage including a coupling member anda latching member together with timed means operated by the movement ofa press part, for releasing the latch under predetermined conditions.Means are provided to set the control for continuous operation or forsingle stroke operation. With the single stroke setting the latch willbe released, irrespective. of the position of the foot pedal, at apredetermined point in the cycle of operations. With the continuoussetting of the controls, the press will run continuously as long as thefoot pedal is depressed. Upon release of the foot pedal, the cycle willbe completed and the press will stop at a predetermined point in thecycle of operation. With the inching control the latch is not permittedto perform its function. The valve will open-whenever the inching leveris operated and will immediately stop when it is released, thuspermitting the press to be moved to any part of the operator of thepress.

its cycle. In the case of the single stroke operation and the continuousoperation, the press will always stop at a predetermined point in itscycle after completing it and will not repeat irrespective of anymovement of the pedal until after the cycle has been completed. Theconstruction is completely mechanical and all of the parts are sturdy,sure of operation and inexpensive to build.

More particularly, referring now to the drawings, a press indicatedgenerally by the reference numeral I may be of any desired type, styleor capacity. Mounted on a side wall I2 of the frame of the press, Iprovide a control valve I4 adapted to be operated by a control lever I6to govern the passage of compressed air through pipe I8 to the clutchand brake operating assembly. It is to be understood that when the valveis opened, the compressed air will cause the motor to drive the presstrain by operating the clutch and releasing the brake.

On the other hand, when the valve I4 is closed, the springs of theclutch and brake assembly will operate to set the brake and release theclutch.

It is to be understood that I have shown my control is applied tooperate a compressed air valve operating lever for purposes ofillustration only and that my control is adapted to be used with anycontrol member known to the art, such as a switch in the case of anelectrically or magnetically operated clutch.

As shown in Fig. 1, the valve is in closed position and held in thisposition by means of spring 22 acting against bushing 24 carried by theoperating lever I6 and reacting against stationary bracket 26 carried bythe press frame. An operating rod 28 must move in the direction of thearrow to rotate the valve operating lever I6 in a clockwise directionagainst the action of spring 22 in order to open the valve.

The rod 28 is moved by actuating lever 30 of a control assemblyindicated generally by the reference numeral 32 shown in greater detailin Figs. 2 to 8 inclusive. The assembly, in turn, is operated through aconnecting rod 34 which is urged upwardly by the action of spring 36acting through a collar 38 secured to the rod 34 and reacting against aflange 40 carried by a connecting assembly indicated generally by thereference numeral 42 and shown in greater detail in Figs. 2 to 8inclusive. A connecting rod 44 is connected at its upper end by theassembly 42 to the rod 34 and at its lower end by the coupling member 46to a foot lever 48 which is fulcrumed at its outer end around pin 50 andis provided at its opposite end with a foot plate 52 adapted to bedepressed by The upper dotted line position of the lever 48 shows theposition of parts when the press is at rest. The lower dotted lineposition of the same foot lever 48 shows the position it occupies whenthe press is started. Upon the depression of the foot pedal, the rod 44will move downwardly pulling rod 34 downwardly against the action ofspring 36 to pivot the actuating lever 30 in a counterclockwisedirection to move rod 28 upwardly against the action of spring 22 aswill be described more fully hereinafter.

The control assembly 32 is provided with a. trip lever 54 adapted tocoact with a cam 55 which is rotated by shaft 56 of the press actuat ingtrain. An inching lever 58 is adapted to be operated by hand to pull rod34 downwardly through a predetermined distance as will be described morefully hereinafter.

Referring now to Fig. 2, I secure a plate 60 to the shaft 56 forrotation therewith. Adjustably mounted upon plate 60 by means of bolts62 I secure the cam 55. The cam is provided with a pair of slots 64adapted to provide angular adjustment of the cam in order to permit thesynchronism of the control mechanism with the operation of the press.The control assembly, which is indicated generally by reference numeral32 in Fig. 1, comprises a pair of plates 66 and 68 between which aremounted a stationary pivoted pawl 10 and a reciprocating pivoted pawlI2, as well as the trip lever 54 and the actuating lever 30, togetherwith pawl biasing means 74 and 16. The reciprocating pivoted pawl 1'2 isan impelling member adapted when pulled downwardly to rotate theactuating lever 30. The base plate 66 of the assembly is secured to thepress frame I2 by means of bolts I8 and 86. A pivot pin 82 is carried bythe base plate 66 around which I pivotally connect the stationarypivoted pawl III. The upper end of connecting rod 34 terminates in astrap 84 which coacts with the lower bifurcated end 86 of reciprocablepawl or impelling member I2, being pivotally connected thereto by meansof pin 88. The impelling member 12 is provided with a slot 90 throughwhich the pin 82 passes and around which the pawl I0 pivots. Thestationary pawl I0 is urged to rotate in a clockwise direction as viewedin Fig. 3 by means of a spring 92 which is housed in the member '14 andacts against bracket 94 secured to the base plate 66 by means of screws96. The spring 92 is lodged about a pin 98 carried by the bracket 94.The biasing member 16 is similar in construction to the biasing memberI4 and urges the reciprocable pivoted pawl I2 to rotate about its pivotpin 82 in a clockwise direction. The upper end of the stationary pawl'II! is provided with a lug I00 which extends across a portion of thereciprocable pawl I2, as can be seen by reference to Fig. 2. Theconstruction is such that a clockwise rotation of the pawl 10 willconstrain the reciprocable pawl to move in a clockwise direction. Theconstruction, furthermore, is such that when the reciprocable pawl movesin a counterclockwise direction the stationary pawl will be forced tomove in a counterclockwise direction.

A pair of posts I02 and I04 are provided for the reception of screws IO6 and I58 to secure the cover plate 68 to the control assembly. A pivotpin I III is provided for the fulcrum of a trip lever 54. A followerroller H2 is pivotally secured to the upper end of the trip lever 54 bymeans of pin II4. The follower roller IIZ is adapted to coact with cam55.

The upper end of reciprocable pawl I2 is bored to receive a shaft II6.Secured to the outer end of the shaft or formed integral therewith, Iprovide a bearing block III The upper end of the reciprocable pawl 12 isprovided with a reentrant portion I20 in which the block H8 is adaptedto seat when it is turned through a 90 angle from the position shown inFigs. 3, 4 and 5, as can be seen by reference to Figs. 6 to 8 inclusivein which the block is shown in the seated position. Secured to the endof shaft I I6 I provide a setting handle I22-which is pinned to theshaft [I5 by means of pin I24. A spring I26 biases the shaft II6 to moveto the left as viewed in Fig. 3.

The position of bearing block H8 can be adjusted to form an extension ofthe surface formed by the right hand side of the reciprocable pawl 12.By rotating the shaft IIIS through 90, the bearing block I I8 may bemoved to a position in which it is housed in the reentrant portion I20.In this position, when the reciprocable pawl I32 and I34. The plate isprovided with a flange 40 against which the lower end of spring 35 isadapted to seat. Pivoted about a pin I35, I provide a plate I38. Thelower end of rod 34 is connected to the plate I33 by means of member I40and pin I42. The upper end of rod 44 is connected to the plate I38 bymeans of member I44 and pin I46. The lower end of rod 44 is connected bycoupling member 45 and pin I45 to the foot lever 48.

Referring now to Fig. 9, a pivoted locking member I48 is pivotallysecured to the frame of the press by bolt I58. lhe locking lever I48 isprovided with a weight I52 which normally pivots the locking lever toposition shown in Fig. 9, that is, the unlocked position. A shoulder I54is formed adjacent the lower end of the lever I48 adapted to coact withthe foot pedal 52 as shown by the dotted lines in Fig. 9, to hold thefoot lever in depressed position for continuous running.

Referring again to Figs. 2 to 8 inclusive, the inching lever 58 ispivoted about pin I35 and is adapted to contact a member I4I carried bypin I42 as can readily be seen by reference to Fig. 2. A stop I56 iscarried by the plate I33 to limit the lower position to which theinching lever can be moved. The inching lever is shown against the stopin Fig. 8. The position of the stop is such as to limit the motion ofthe reciprocable pawl downwardly to prevent the latching of theactuating lever by thestationary pawl 19-.

In operation, referring now to Fig. 3, in which the parts are shown inidle position with the press stopped, the bearing block II8 has beenadjusted to the single stroke position, the valve I4 is closed, theactuating lever being in the position it occupies when the valve iclosed. The toe of the actuating lever 35 is engaged with the projectionof the reciprocable pawl I2. The foot pedal is in raised position beingurged upwardly by the action of spring 35 acting through connectingplate I38 and rod 44.

Let us assume it is now desired to operate the press for a singlestroke. The foot lever 48 is rotated in a counterclockwise direction bystepping upon foot pedal 52, thus pulling the rod 44 downwardly androtating the connecting plate I38 in a counterclockwise direction. Thispulls rod 34 downwardly against the action of spring 35, pulling thereciprocable pawl "I2 downwardly. Since the pawl I2 isengaged with thetoe of actuating lever 33, it will rotate this lever in acounterclockwise direction, pulling the rod 28 upwardly against theaction of spring 22 and rotating the valve operating lever I6 in aclockwise direction to open the valve. The stroke of the movement of thepawl 12 is such that it carries the toe of the actuating lever 33downwardly past the upper portion of latching pawl It camming it torotate in a counterclockwise direction around pivot pin 82 against theaction of spring 52 exerted through pawl biasing member E4 andunderneath the projection at the upper end of latching pawl Ill to holdthe actuating lever 33 in the position shown in Fig. 4.- The valve beingopen permits compressed air to operate the clutch causing the press torun. It will be observed that if the foot pressure upon pedal 52 isreleased, the reciprocable pawl I2 will again move upwardly to theposition shown in Fig. 3. The lower toe of the trip lever 54, it will benoted, contacts with the pawl itself as shown in Fig. 3 or the bearingblock II 8 as shown in Fig. 4 when the bearing block is set for thesingle stroke position, and the foot pedal is held depressed.

As the press runs, it will rotate shaft 56 in a counterclockwisedirection carrying the cam 66 around until it reaches the position shownin Fig. 5, in which the parts are shown with the foot pedal depressedbut with the bearing plate I I8 set in single stroke position. The cam55 has rotated the trip lever 54 in a clockwise direction so that itstoe acting against bearing plate II8 pivots the reciprocable pawl 12around pin 82 in a counterclockwise direction. The reciprocable pawl 12in this movement engages the lug I03- carried by the latching pawl '40and rotates this pawl in a counterclockwise direction, thus freeing thetoe of actuating lever 36 and permitting the spring 22 to move rod 23downwardly to rotate the valve operating lever I 5 in a counterclockwisedirection to close the valve M. It will be observed that it isimmaterial whether or not the foot pedal 52 is held in depressedposition or not. The press will always stop after completing one stroke.The trip lever 54 acts against bearing block III! when the foot pedal isdepressed and the trip lever 54 acts against the reciprocable pawlitself when the foot pedal is raised.

For continuous operation, the bearing block I 18 is housed as shown inFigs. 6 to 8 inclusive. Referring now to Fig. 6, in which the parts areshown with the press running and the foot pedal held downwardly bymeans. of the latch I48, it will be observed that the actuating lever 33has its toe latched in running position by the pawl 13. The trip lever54 is clear of the cam 55 so that rotation of the press will notactuate. the trip lever 54 to cause the reciprocable pawl 12 to berotated in a counterclockwise direction. The housing of the bearingblock H8 removes the surface through which the lower toe of trip lever54 acts. The press will run continuously with the parts in the positionshown in Fig. 6.

Let us now assume that it is desired to stop the press with the bearingblock 9 i3 housed, that is. in the continuously running position. Thisis accomplished by releasing the foot lever latch I48 so that the pedalwill move to its upper position as shown in '7. This permits thereciprocable pawl 32 to move upwardly to the position shown in Fig. '7.The upward motion of the reciprocable pawl cams the trip lever 54 tomove in a counterclockwise direction raising the roller H2 into the pathof the cam When the cam moves around to its predetermined position, itwill rotate the trip lever in a clockwise direction around its pivot pinHi3 forcing the reciprocable lever to rotate around its pivot pin 32 ina counterclockwise direction and carrying with it the latching pawl itthrough the lug I56 formed thereon, thus releasing the toe of theactuating lever 30. The press will stop at its predetermined position inaccordance with the motion of the cam.

When it is desired to inch the press and move it to any desired point inits cycle, the inching lever is operated. Rotation of the inching leverin a counterclockwise direction around its pivot pin 36 will move thereciprocable pawl 72 downwardly carrying with it the toe of theactuating lever 30 causing it to rotate in a counterclockwise directionaround its pivot pin 3| to lift the connecting rod 28 and thus operatethe valve operating lever Hi. It will be observed, however, that theinching lever 58 has a predetermined limit of motion governed by thestop I55. This limit is such that the downward motion of thereciprocable pawl I2 is above that at which the toe of the actuatinglever.39 would be latched downwardly by the pawl 10. The result is thatwhen the inching lever is released the valve immediately closes. it isimpossible to cause the press to run except when the inching lever isdepressed. It will not complete a cycle unless the inching lever is helddownwardly during the entire cycle. As soon as the inching lever isreleased, since the latching pawl 10 is ineffective, the valve willclose under the influence of spring 22 which moves the valve operatinglever 6 to rotate in a counterclockwise direction thus closing thevalve.

It will be seen that I have accomplished the objects of my invention. Ihave provided an improved mechanical trip control for presses capable ofcontrolling the press for a single stroke operation, continuousoperationand inching operation as desired. My control is completelymechanical and is certain in its operation and capable of operating forlong periods of time Without breakdown necessitating repairs. Mymechanical trip control is simple in its operation and inexpensive tomanufacture. The parts are sturdy and visible. My press can beaccurately adjusted to stop the cycle within predetermined limitsdetermined by the setting of the cam 55.

I have described my trip control with respect to presses for purposes ofillustration. It is to be understood that my trip control may be appliedto any machine driven by a primary mover through the agency of a fiywheel and clutch such as machine tools, printing presses, hoistingequipment and the like.

It will be understood that certain features and sub-combinations are ofutility and may be employed without reference to other features andsub-combinations. This is contemplated by and is within the scope of myclaims. It is further obvious that various changes may be made indetails Within the scope of my claims without departingfrom the spiritof my invention. It is, therefore, to be understood that my invention isnot to be limited to the specific details shown and described.

Having thus described my invention, what I claim is:

1. A control assembly for power presses including, in combination, anactuating lever for controlling the press, an impelling member havingoperative engagement with said actuating lever, a detent adapted to holdsaid actuating lever in press operating position, a trip lever adaptedto release said detent, means coupling said detent and said impellingmember whereby movement of said impelling member in a predetermineddirection will drive the detent to actuating lever releasing position,said impelling member being formed with a surface adapted to engage saidtrip lever when the impelling member is in press stopping position,adjustable means carried by said impelling member adapted selectively tobe moved to a position engaging the trip lever when said impellingmember is in press running position whereby the control assembly may beadjusted for single cycle operation or for continuous operation andmeans responsive to The arrangement is such that V the movement ofa'press part for actuating said trip lever at a predetermined point ofthe press operation cycle.

2. In a control assembly for power presses, an actuating lever forcontrolling the press, a manually operable reciprocable member havingengagement with said actuating lever and adapted to move it to pressrunning position, a detent adapted to engage said actuating lever tohold it in press running position, a detent trip lever, means responsiveto the movement of a press part for driving said trip lever, meanscarried by said reciprocable member coacting with said trip lever andmeans providing an operable connection between said reciprocable memberand said detent to release said actuating lever in response to motion ofsaid trip lever.

3. A control assembly for power presses including in combination acontrol member adapted to be actuated to control the operation of apress, an actuating lever for operating the control member, an impellingmember having operative engagement with the actuating lever, a detentadapted to hold the actuating lever at press operating position, a triplever adapted to release the detent, means coupling the trip lever andthe detent, a cam for driving the trip lever, means for mounting the camfor movement as a function of the movement of a press part, manuallyoperable means for moving the impelling member to start the operation ofthe press, said means coupling the trip lever and the detent includinginterengageable means carried by the impelling member and the detent andan adjustable surface carried by the impelling member adapted to contactthe trip lever when the impelling member is in a position moving theactuating lever to press running position.

4. A control assembly for power presses including in combination acontrol member adapted to be actuated to control the operation of apress, an actuating lever for operating the control member, an impellingmember having operative engagement with the actuating lever, a detentadapted to hold the actuating lever at press operating position, a triplever adapted to release the detent, means coupling the trip lever andthe detent, a cam for driving the trip lever, means for mounting the camfor movement as a function of the movement of a press part, manuallyoperable means for moving the impelling member to start the operation ofthe press, said means coupling the trip lever and the detent includinginterengageable means carried by the impelling member and the detent andan adjustable surface carried by the impelling member adapted to contactthe trip lever when the impelling member is in a position moving theactuating lever to press running position, the adjustable surfacecomprising a bearing block, means for supporting the bearing blockadjacent the upper end of the impelling member, said upper end beingformed with a recess and means for housing the bearing block in therecess to set the control for continuous operation.

5. A control assembly for power presses including in combination acontrol member adapted to be actuated to control the operation of apress, an actuating lever for operating the control member, an impellingmember having operative engagement with the actuating lever, a detentadapted to hold the actuating lever at press operating position, a triplever adapted to release the detent, means coupling the trip lever andthe detent. a cam for driving the trip lever, means for mounting the camfor movement as a function UNITED STATES PATENTS of the movement of apress part and manually Number Name Date operable means for moving theimpelling member 945,551 Knee Jan 4, 1910 to start the operation of thepress, the manually 1,600,403 Dorman et a1 Sept. 21, 1926 operable meansfor moving the impelling memberv 5 1,655,617 Lindgren Jan 10, 1928comprising a foot lever, a second manually ope'r- 1,681,646 Papas 21,1928 able means for moving the impelling member 2,052,752 criley Sept 1,1936 and a stop for limiting the motion of the second 2,204,710 stroutJune 18 1940 manually operable means to render the detent 2,217,332Criley Oct 8, 1940 lnefiective to latch said actuating lever upon the 102,342,645 Criley Feb 29 1944 operation of the p ne m m er. 2,494,452Pearson Jan 10, 1950 VASIL GEORGEEF.

REFERENCES CITED The following references are of record in the 15 fileof this patent:

